Effects of PACAP on the circadian changes of signaling pathways in chicken pinealocytes.

摘要: Pituitary adenylate cyclase-activating polypeptide (PACAP) is involved in the regulation of circadian rhythms. In mammals, brain’s biological clock suprachiasmatic nucleus, receiving photic information from retina through retinohypothalamic pathway, where PACAP main cotransmitter glutamate. The primary conductor rhythms birds pineal gland. presence has been demonstrated both rat and avian gland, stimulates melatonin synthesis. signaling mechanism, by which modulates synthesis rhythmic functions only partially known. aim present study was to investigate effects on changes p38 mitogen-activated protein kinase (MAPK) 14-3-3 chick cell culture have shown participate functions. Pineal cells were treated with 1, 10, or 100 nM PACAP38 every 4 h during a 24-h period. phosphorylation MAPK showed obvious observed 24 h, while level did not. We found that lowest used dose not cause any phase alteration phosphorylation. Ten induced 4-h-long delay abolished effective early morning hours, highest tested (100 nM) could evoke change appearance between midday midnight hours. summary, modulated chicken cells, but these dependent also depended time day.